Merck Shares Slip As Blood Cancer Drug Study Enrollment Paused

Merck & Co. shares slipped in the extended session Monday after the drug maker announced its was pausing enrollment in studies of a cancer treatment at the recommendation of a data monitoring committee. Merck shares declined 1.2% to $63.60 after hours. The company said it paused patient enrollment in two studies following its drug Keytruda for the treatment of blood cancer multiple myeloma. The pause in enrollment is meant to study why certain patients given Keytruda died, Merck said.